Level



Sm. 25,19%. @www A. C. ELLIOTT LEVEL Filed Jan. 30 1922 Elm/venin@ ffnung@ Patented Sept. 25, 1923.

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ALVIN ELLIOTT, 0F GRAND FORKS, NORTH DAKOTA.

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Application filed January 30, 1922. Serial No. 532,703.

To all whom z't may concern.'

Be -it -known that I, AnvIN C. ELuoT'r, a citizen of the United States, residing at Grand Forks, in the county of Grand Forks and State of North Dakota, have invented certain new and useful Improvements 1n Levels, of which the following is a specification.

This invention relates to levels of the gravity type, in which a swinging gravity actuated bob or pointer is utilized in lieu of the ordinary spirit level tube, and the primary objects of the present invention are, first, to provide a novel gravity level which can be used effectively as a miter square, and which will givethe anule of inclination of a surface on which the level is placed; second, to provide a novel means for mountin@ the bob or pointer in the stock; and third, to provide a novel means for incor orating the protractors which cooperate with the bob or pointer and the protecting glasses in the stock, said means allowing the quick and easy association of the various parts in the stock.

A further object of the invention is to provide an improved gravity level of the above character, which will be durable and efficient in use, one that will be simple and easy to manufacture, and one which can be placed upon the market at a reasonable cost.

With these and other objects in view, the invention consists in the novel construction, arrangement and formation of parts, as will be hereinafter more specifically described, claimed and illustrated in the accompanying drawings, forming a part of this specification, in which drawings:

Figure 1 is an elevation of the improved level.

Figure 2 is a central transverse section through the same, taken on the line 2-2 of Figure 1.

Figure 3 is a fragmentary longitudinal section through the improved level taken on the line 3-3 of Figure 2.

Figure 4 is an enlarged fragmentary transverse sectional view through the improved level, illustrating the means of incorporating the bob or pointer with the stock, to permit the free swinging movement thereof, and

Figure 5 is a detail transverse section taken on the line 5 5 of Figure 4.

Referring to the drawings in detail,

wherein similar reference characters desig nate corresponding parts throughout the several views, the letter A indicates the improved level, which includes the stock B, the pointer or bob C, the protractor plates D and E, the protecting glasses F, and the retaining rings G.

r1`he stock B can be of any desired len h and formed of any desired material, pre erably of hard wood, such as mahogany or maple and the terminals of the stock can be provided, if so desired, with end caps 10. The longitudinal edges 11 of the stock, are of course provided with smooth plane outer surfaces, which are arranged in parallel relation to each other. The stock B, at a point intermediate its ends, is provided with a transverse opening 12 and the wall of the opening at the opposite ends thereof is rabbeted-as at 13, to provide the stop shoulders 14.

The pointer or bob C includes a hinge barrel 15, a depending shank 16, and a weighted indicating arrow shaped head 17. The barrel 15 has one end thereof closed 'by an end wall 18, which is provided with a concentric opening for the reception of the su porting shaft 19. The opposite end of the arrel 15 is provided with a closing cap 20, which is provided with a concentric opening for receiving the shaft 19. The cap 20 can be held in position by suitable retaining elements, such as machine screw 21. In order to permit the free Swingin movement of the pointer or bob C, suita le anti-friction elements, such as roller bearings 22, are interposed between the shaft 19 and the barrel 15, as clearly shown in Figures 4 and 5 of the drawings. The shaft 19 can be formed of'hard tool steel, but it is referred that the pointer or bob C be forme of brass or some other metal, which will not be attracted by magnetic influences. The terminals of the shaft 19 extend beyond the barrel 15 and it is preferred that these shaft terminals be seated in friction plugs 23, such as rubber, which may be embedded in the protecting glass plates F, which will be hereinafter .more fully described.

The plates F are preferably formed of plate glass, but an other suitable transparent material may e utilized, such as eelluf loid, or the like, and these plates are of a disc formation and have the inner faces thereof provided at their axial centers with recesses 24 for the reception ofthe plugs 23. It can be seen that thezplugs 23 will tend to hold the shaft 19 against rotation. Thrust bearings 25 can be provided for-the terminals of the barrel 15, and these thrust bearings consist of ball bearing races 26, which are mounted upon the shaft 19, and these races support ball bearlngs 27, which are adapted to engage the outer surface of the cap 2O and the outer surface of they end wall 18 of the barrel. sired, washers 28 may be placed on the shaft terminals intermediate the ball bearing races .which may be graduated to define the degrees of a circle, and these annular plates sists of annular 26, and the protecting glass plates F, and the inner faces of these washers may be ground smooth or polished, while the outer\ faces may be left rough for frictionally engaging the plugs 23.

The protraetors D and E, are of course, constructed identically the same, and 1nclude annular plates 30, the outer faces of may be formed of metal or any other suitable material possessing the necessary qualifications. These protractors D and are adapted to fit against the shoulders 14 1n the rabbeted portions 13 of the stock C, and after the same has been placed 1n positlon, the protecting plates F are then placed' 1n the rabbeted portions 13 against the same. It is preferred that annular resilient frlction rings or seats 31 be provided for the edges of the transparent plates F, and these seats are preferably formed of soft rubber, having the inner faces thereof grooved as at 32, in which the plates F are adapted to fit. It can be seen that these seats 31 not only tend to hold the transverse plates in position, but also form a soft seat for the same so as to prevent breakage thereof.

The means G provided for holding the various parts of the level in position conplates 33 and 34, which fit against the opposite faces of the stock B, and extend inwardly of the walls of the opening l2 andengage the resilient seats 3l of the transparent plates F and hold these plates and the other portions of the level against displacement. The plates 33 and 34 can be made of metal and are held in position against accidental displacement by suitable retaining elements, such as wood screws, 35.

It is apparent from the foregoing, that an exceptionally simple means has been provided for holding the various-parts of the level in position, said means allowing the quick and easy assembling of the said parts.

In assembling of the level, one of the protractors, say the protractor D is first placed in position against one of the shoulders 14, after which the protecting plate is placed against the same, and the retaining ring 33 screwed into position.' The barrel 15 is then placed on vthe shaft 19 and one of the ball bearing races 25 is placed on the shaft termi- If so denal, and a washer 28 placed against the same. A friction plug 23 is then placed in the opening 24 in the glass plate which has been placed in position and the mentioned shaft terminal 19 is inserted in the plug. After this shaft 19 has been placed in position, the other ball race 25 may be placed on the other shaft terminal with the washer 28 against thesame. The other glass plate is then inserted in the rabbeted portion at an incline until the other shaft terminal rides into the socket provided in the resilient plug 23 after which the plate may be clamped in position by the ring 24.

It also can be seen that the manner of mounting the bob or pointer D allows the freer swinging movement thereof under all conditions and thus a true reading of theJ bob or pointer may be at all times obtained.

Changes in details may be made without departing from the spirit or scope of this invention; but,

I claim:

l. A gravity level comprising a stock having a transverse opening therein, the wall of the opening having its opposite ends rabbeted thus providing stop shoulders, annular protractor plates fitted in the rabbeted portions against said shoulders, transparent guard plates fitted in the rabbeted portions against said protractor plates, the inner faces of the transparent guard plates having axially disposed recesses formed in the inner faces thereof, friction socket plugs fitted in said recesses, an axially disposed shaft having its terminals disposed in the friction sockets, removable means for holding lthe transparent plates in position in said rabbcted port-ions against said prot-ractor plates, a gravity operated bob including a barrel for receiving said shaft, an indicating head, and a connecting shank, bearings disposed between the barrel and the shaft, and thrust bearings disposed on said shaft intermediate the barrel and the transparent plates and the friction plugs carried thereby, the friction plugs forming means for holding the shaft against rotation.

2. A gravity level comprising a stock having a centrally disposed transverse opening therein, the wall of the opening having its opposite ends provided with rabbetedportions defining stop shoulders, annular protractor plates disposed in the rabbeted portions against said shoulders, transparent guard plates, annular friction seats surrounding the edges of said transparent plates, the plates being fitted in the rabbetedl portions against said protractor plates, removable retaining rings secured to the stock and engaging the annular friction ing-its terminals fitted in said sockets, a

gravity operated pointer including a barrel, an indicating head, and a connecting shank, the barrel being fitted upon the shaft, roller bearings disposed in said barrel around said shaft, washers disposed on said shaft and engaging said friction sockets, and thrust -bea-rings disposed about said shaft and engaging said Washers and the terminals of said barrel, the friction sockets forming means for holding the shaft against rotation.

3. A lever comprising a stock having a transverse opening therein, annular graduated plates disposed in said opening at the opposite ends thereof, transparent guard posed between the shaft and the barrel, and thrust bearings disposed on the shaft intermediate the transparent guard plates and the terminals of the barrel',

4. A gravity level comprising a stock having a central-ly disposed transverse opening therein, the Wall of the opening having its opposite ends provided with rabbeted .por-A tions defining stop shoulders, annular protractor plates disposed in the rabbeted portions againstsaid shoulders, transparent guard plates, annular friction seats surroundi ing the edges of said transparent plates, the plates being fitted in the rabbeted portions against said protractor plates, removable retaining rings secured to the stock and engaging the annular friction seats, the transparent plates having the inner faces thereof provided with axially disposed recesses, fric-` tion sockets fitted in said recesses, -a transversely disposed shaft having its ternnnals fitted in said sockets, and a gravity operated 'bob carried by said shaft.

ALVIN C. ELLIOTT. 

